I want to make asynchronous multiple-channel acquisition with alarm notification

[Kristijan]

I want to make a system which measures voltages form 8 channels, and if any of those meet the alarm-on condition i specify then a callback function is called which, for example, must set digital output to HIGH. To be more specific, if AI0 goes above 2V then DO0 is set HIGH, if AI4 goes above 3V then DO4 is set HIGH.

I am trying to use Config_Alarm_Deadband + double-buffered acquisition + DAQ_Start but DAQ_start reads only one channel, but i need to read from 8 channels.

Can anyone tell me how can i do that?
I am writing in Microsoft Visual C++ and using MFC. So if anyone has some sample code, please send me.

Thanks in advance.

[Sastry V.]

Hi,
In order to perform the multiple channel acquisition, please take a look at the commands starting with SCAN, such as, SCAN_Start.

And regarding the examples, there are two places I would suggest you to take a look at :

1. In your C:\program files\national instruments\ni-daq\examples\visualc folder

2. Go to www.ni.com, Developer Zone, Development Library and the Measurement Hardware.

Please do let me know if you still have any questions.

Sincerely,
Sastry V.
Applications Engineer
National Instruments.